How do I stay steady through incidents and contraband on the job?

You can maintain security now, and the routine no longer rattles you. What tests you are the incidents and the contraband, the moments when the calm breaks and things could go wrong fast. That those still test you is not a weakness. In your line of work, the person who stops feeling anything at those moments is the one who becomes dangerous, to themselves and others. The skill at the sharp edge is not to feel no fear but to have your training run deeper than the fear. When an incident hits, you do not want to be improvising; you want to fall back on procedure you have rehearsed until it is automatic. That is what lets you act clearly while your heart is pounding. Steadiness under pressure is built quietly, in the drilling you do before the moment ever comes. So keep your training sharp on purpose, and after each incident, take a few minutes to review what happened, not to punish yourself but to learn. Talk it through with someone who was there. The incidents will keep coming; that is the job. What changes is that each one you handle and reflect on makes the next one a little less able to shake you.